<!doctype html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Document</title>
	<style type="text/css">
	#input{
		display: block;
		margin:30px auto;
		width: 650px;
		}	
	#input #in{
		border:1px solid #4791ff;
		width:540px;
		height:36px;
		margin:auto;
		font-size:19px;
		display:block;
		float: left;
		}	
	#sub{
		width:100px;
		height:38px;
		background:#2d78f4;
		float:left;
		display:block;	
		border:0px;	
		color:#fff;
		font-size: 19px;
		padding-left:15px;
		padding-right:15px;
		}
		</style>

</head>
<body>
  <div id="input">
    	<input id="in" type="text"/>
        <input id="sub" type="button" value="百度一下"/>
    </div>
</body>
</html>